# -*- coding: utf-8 -*-

# Define here the models for your spider middleware
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/spider-middleware.html

from scrapy import signals
from scrapy.http.headers import Headers
from csdn_blog import user_agent


class CsdnBlogSpiderMiddleware(object):
    # Not all methods need to be defined. If a method is not defined,
    # scrapy acts as if the spider middleware does not modify the
    # passed objects.

    @classmethod
    def from_crawler(cls, crawler):
        # This method is used by Scrapy to create your spiders.
        s = cls()
        crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
        return s

    def process_spider_input(self, response, spider):
        # Called for each response that goes through the spider
        # middleware and into the spider.

        # Should return None or raise an exception.
        return None

    def process_spider_output(self, response, result, spider):
        # Called with the results returned from the Spider, after
        # it has processed the response.

        # Must return an iterable of Request, dict or Item objects.
        for i in result:
            yield i

    def process_spider_exception(self, response, exception, spider):
        # Called when a spider or process_spider_input() method
        # (from other spider middleware) raises an exception.

        # Should return either None or an iterable of Request, dict
        # or Item objects.
        pass

    def process_start_requests(self, start_requests, spider):
        # Called with the start requests of the spider, and works
        # similarly to the process_spider_output() method, except
        # that it doesn’t have a response associated.

        # Must return only requests (not items).
        for r in start_requests:
            yield r

    def spider_opened(self, spider):
        spider.logger.info('Spider opened: %s' % spider.name)


class CsdnBlogDownloaderMiddleware(object):
    # Not all methods need to be defined. If a method is not defined,
    # scrapy acts as if the downloader middleware does not modify the
    # passed objects.

    @classmethod
    def from_crawler(cls, crawler):
        # This method is used by Scrapy to create your spiders.
        s = cls()
        crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
        return s

    def process_request(self, request, spider):
        request.headers = Headers(
            {
                'User-Agent': user_agent.get_user_agent_pc(),
                'Cookie': 'uuid_tt_dd=10_20345766140-1557466352010-151600; dc_session_id=10_1557466352010.906982; __yadk_uid=nKjYgM5lULHdwuPpQLSYMMGafgy4cnsI; acw_tc=2760826015707590543522431e93e1dd9fffaedda271bfc936097f95d372cb; UserName=Stannis; UserInfo=34ef7e80fe2044fba59c9e317f4b6e80; UserToken=34ef7e80fe2044fba59c9e317f4b6e80; UserNick=Stannis; AU=808; UN=Stannis; BT=1570778173186; p_uid=U000000; Hm_ct_6bcd52f51e9b3dce32bec4a3997715ac=6525*1*10_20345766140-1557466352010-151600!5744*1*Stannis; Hm_lvt_6bcd52f51e9b3dce32bec4a3997715ac=1571127225,1571290936,1571726709,1571794377; announcement=%257B%2522isLogin%2522%253Atrue%252C%2522announcementUrl%2522%253A%2522https%253A%252F%252Fblogdev.blog.csdn.net%252Farticle%252Fdetails%252F102605809%2522%252C%2522announcementCount%2522%253A1%252C%2522announcementExpire%2522%253A215368526%257D; TY_SESSION_ID=db3c8de0-538c-4da8-b27e-73f33a3e227d; acw_sc__v2=5db01b8a9c3e8dd80c5c975c19e33d174900fd8f; acw_sc__v3=5db01b8c8a9fd33a1183dc9d08e7fd7b74ecfcf3; dc_tos=pztm0h; Hm_lpvt_6bcd52f51e9b3dce32bec4a3997715ac=1571822515',
            }
        )

        print('CsdnBlogSpiderMiddleware启动')
        # Called for each request that goes through the downloader
        # middleware.

        # Must either:
        # - return None: continue processing this request
        # - or return a Response object
        # - or return a Request object
        # - or raise IgnoreRequest: process_exception() methods of
        #   installed downloader middleware will be called
        return None

    def process_response(self, request, response, spider):
        # Called with the response returned from the downloader.

        # Must either;
        # - return a Response object
        # - return a Request object
        # - or raise IgnoreRequest
        return response

    def process_exception(self, request, exception, spider):
        # Called when a download handler or a process_request()
        # (from other downloader middleware) raises an exception.

        # Must either:
        # - return None: continue processing this exception
        # - return a Response object: stops process_exception() chain
        # - return a Request object: stops process_exception() chain
        pass

    def spider_opened(self, spider):
        spider.logger.info('Spider opened: %s' % spider.name)
